Adjustable sockets of the type driven by a ratchet or unitary wrench having a bent end that is received within a wrench opening are known in the prior art and may be used to replace more conventional socket sets which include a number of differently sized sockets for driving bolts and nuts of different sizes. Adjustable sockets are also disclosed in the prior art which are usable with straight wrenches having a handle end like a screwdriver or slidable wrench handle of the type normally used on hand taps.
Adjustable sockets generally include a set of jaws that are readily movable to receive and drive nuts and bolts of a range of sizes. Because the jaws can be adjusted to any position within the socket's adjustment range, it is possible to accommodate both English and Metric size nuts and bolts when the socket is appropriately adjusted. Thus, a mechanic can work on any particular job with a single adjustable socket without having to frequently remove one socket from the wrench and replace it with another socket. The use of a single adjustable socket also eliminates time consuming searches for sockets of a particular size, as well as the need for both English and Metric conventional socket sets.
While a variety of different adjustable sockets are known in the prior art, previous designs have had various disadvantages. Such disadvantages include sockets which have been difficult to manufacture, some which were not adaptable to a three-jaw construction and many which had particularly complex designs.
U.S. Pat. Nos. 4,213,355, 4,366,733 and 4,378,714 to Colvin, for example, disclose adjustable sockets wherein the jaws are mounted in driver slideways for inward adjusting movement against a spring bias and for outward adjusting movement under the impetus of the spring bias. This adjusting movement is provided by rotation of an adjuster having a helical locking surface that engages a helical locking surface on the driver to move a sleeve that has camming surfaces engaged with camming surfaces of the jaws. While this type of adjusting socket has achieved significant commercial success, the inward and outward adjusting movement involves spring bias making the socket complex in design and manufacture.
U.S. Pat. No. 4,608,887 to Colvin and U.S. patent application Ser. No. 07/092,437 to Cox et al. also disclose adjustable sockets which have received significant commercial acceptance. These sockets also each include jaws mounted in driver slideways. In each case adjusting movement of the jaws is provided by rotation of an adjuster having a jaw operating member with a radially extending annular flange which engages a radial slot in each jaw. The jaw operating members each engage a rotatable adjusting member having helical threads that engage helical threads on the driver to move the jaws upon rotation of the adjuster. One disadvantage of these designs, however, has been the problem of maintaining the jaws positioned within the slideways during opening and closing movement, as well as the disadvantage of being difficult to efficiently assemble.